The opportunity to make an employer-sponsored international move can be hard to resist. Why would anyone refuse the chance to take an exciting position in a new country and be well paid in the process? An expat assignment can feel like the perfect opportunity to advance professionally; it can also hold the prospect of a thrilling adventure – on your own or together with your partner and/or family.

There are, however, good reasons to say ‘no’ to an international assignment, and a failure to do so can exact a serious cost – on your career, your relationships or both. When professionals move internationally, many struggle or fail. One indicator of failure is early return: up to 10% of expat assignments are terminated early. And even if they don’t fail outright, the wrong assignment at the wrong time can undermine your long-term career prospects and have a negative impact on your relationship with your partner and the wellbeing of your family.

How do you know whether you should say no? Here are five reasons not to take an international assignment. Any one of them is a red flag; two or more increase the risks significantly.

1. Your partner is not really on board

One set-up-to-fail scenario is when the assignment is a good deal for you, but not for your partner. Whether the negative impacts are career-related, personal, social or a combination, or if your partner feels like they did not have a say in the decision, they are more likely to become resentful and resistant to adjusting. While they may suppress their doubts and go along, too often ‘trailing partners’ regret it later on. If your motives are not sufficiently aligned with your partner’s, inevitably it will poison the move. So don’t take that assignment unless you are both on board with the decision and committed to making the move a success.

If you are part of a dual-career couple, being on the same page before deciding on an international move is even more crucial. Both of you may have careers that are just taking off, and so be reluctant to leave it. If your partner’s career is not portable, they will have to start over in the new location, with an uncertain future. Worse, they may want to work, but not be legally allowed to do so because of visa or other restrictions. Whatever the particulars of your situation, the prospect of one’s career suffering because of relocation could be a source of deep resentment.

2. The adjustment challenges for your family will be too great

Even if your partner is willing to sign up, you still need to think through the implications for the well-being of your family. About 70% of expat executives move with a partner or spouse, and it is often the partner’s – or family’s – inability to acclimate to the new environment that is the root cause of failure. Surveys from leading mobility companies show that executives’ most cited reason for giving up a foreign posting is ‘family concerns’, including adjustment difficulties, children’s education challenges, quality of life, and lack of practical support. Here are some examples of potential ‘red flags’:

· You plan to start a family and the move would take you far away from your support system (extended family, network of close friends).

· Your destination does not offer adequate options for your children’s education, and there are no acceptable alternatives (such as boarding school).

· You have teenagers at home and an international move would uproot them from their familiar environment and circle of friends at a critical time in their lives.

· You have children who require special care (for example, due to a medical condition, physical disability or learning difficulty) which cannot be accommodated in the new location.

· Your assignment would take you thousands of miles away from ailing parents or other family members, undermining your ability to communicate and help care for them.

Even when you don’t have family concerns, there still can be good reasons to say no.

3. The move will not fulfil your longer-term goals

Ask yourself: Will this move really advance my long-term career and life objectives? If you move in order to improve your finances, a higher salary may not necessarily translate into that if your cost of living is higher or you have to pay higher taxes. If you move to advance your career, consider the long term – not only the current move, but the next one, and the one after that. Even if the current move is great for your career, does it open up options for you down the road and position you to fulfill your long-term career objectives? If not, then think again. Also, if the assignment does not work out, will there be other opportunities for you in the new location or will you have to move – back home or elsewhere? If it’s the latter, will you have been able to maintain your professional relationships and network back home? If you move to improve your quality of life, look beyond country ratings and into your particular circumstances. If your prestigious new position requires a substantial amount of travel, your social life may suffer, for example.

If you are considering an international move, but have no interest in becoming a lifelong expat, think hard before you say ‘yes’. Very often one assignment leads to another and then another and, before you know it, going back to your previous life is no longer an option. There’s a reason for the saying “once and expat, always an expat.”

4. You don’t do well with change

Living and working abroad is guaranteed to require you to step out of your comfort zone, deal with uncertainty, and break with established patterns of thought and behavior. While all that can have immense benefits for your personal growth and resilience, it can also be emotionally taxing and cause you high levels of distress if your personality is not built for it. If you have low tolerance for ambiguity and uncertainty; don’t like surprises; or thrive in stable, predictable environments and need a high degree of control over your life to feel comfortable, don’t say ‘yes’ to an international move unless you feel prepared to deal with the kind of stress it is likely to bring.

5. You are unlikely to feel comfortable or safe at your destination

Finally, if your destination does not provide what you need to feel safe and at home, then this might not be the right move. The new culture may be extremely different from the one you are accustomed to; or may have values and beliefs that clash with your own. There may be a significant language barrier. The society may not be welcoming to foreigners or to singles like you. All that can affect your sense of belonging, your ability to function effectively, make friends and find home, among others. Or moving may affect your health, including pre-existing health conditions (that may be worsened by climate, for example), your ability to sleep enough, exercise regularly and engage in other activities that are important to your physical and emotional wellbeing. Think about the kind of life you want for yourself and don’t make a move that will not improve – or at least maintain – your quality of life.

Similarly, ‘no’ may be the right answer if you have concerns about safety at your destination. If the new culture and society is likely to be unfriendly or even dangerous for you; if you are likely to be viewed negatively, discriminated against, be subject to violence or even get in trouble with the law, based on your gender identity, race, sexual preference or other minority status, then a different destination may make more sense.

What’s the bottom line? Don’t say ‘yes’ to an expat assignment just because it’s exciting or expected of you. Whether you have three weeks or three days to think through the consequences, and whether it is your first expat move or your tenth, it’s essential to think long-term, consider goals and implications, and take into account the impact on everyone who moves, if relevant. Making an international move is a life-changing decision. Make sure you have a compelling ‘why,’ and look before you leap.